Employee Share Ownership Plans - Summary of Description of Plans (Parenthetical) (Detail)	12 Months Ended
	Jun. 30, 2025 USD ($) Awards
Shareplus [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	3 years
Maximum employee contributions to acquire shares \| $	$ 5,000
Long-Term Incentive Plan [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	5 years
Vesting percentage	100.00%
Long-Term Incentive Plan [member] \| Peer Group Total Shareholder Return [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	67.00%
Long-Term Incentive Plan [member] \| Index Total Shareholder Return [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	33.00%
Long-Term Incentive Plan [member] \| Median Total Shareholder Return [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	25.00%
Long-Term Incentive Plan [member] \| Bespoke Sector Peer Group [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	67.00%
Long-Term Incentive Plan [member] \| MSCI World Index [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting percentage	33.00%
Cash and deferred plan [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of deferred award tranche \| Awards	2
Cash and deferred plan [member] \| First tranche [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	2 years
Cash and deferred plan [member] \| Second tranche [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	5 years
Bottom of range [member] \| MAP awards [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	1 year
Top of range [member] \| MAP awards [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Vesting period	5 years